At the present time, vehicle heated glazing, and particularly rear screens, receive their supply of electrical current through a pre-tinned connection and the cable is electrically soldered to the glazing at an advanced shop, that is to say on the vehicle production and assembly line, by the motor manufacturer.
This is impractical and motor manufacturers have high hopes of being able to fit, directly into the opening in the bodywork, glazing that is ready to be connected to the rest of the vehicle electrical system.
The glass maker therefore supplies the motor manufacturer with glazing comprising a male element already fixed to the glazing, and once the glazing has been fitted into the opening in the bodywork, all that is then required is for a female connection element to be clipped onto the male element in order to connect the electrical elements of the glazing to the wiring harness of the vehicle. Electrical connection to the surface of the glazing is thus performed at an advanced shop, by clip-fastening.
This solution makes it easier to pre-assemble the wiring harness using a clip-fastened rather than a soldered, electrical connection.
There is thus no longer any need to have skilled soldering performed in the various advanced shops, the electrical connection therefore becomes more reliable, the risk of glazing cleavage is eliminated, and it becomes possible to standardize the connection (which then becomes the same for all functions): antenna, heating, opening command, brake lights, etc.
A male connector and a female connector which could be used for the abovementioned application are known from the prior art, from American patents U.S. Pat. No. 6,039,616 and U.S. Pat. No. 6,520,812, respectively.
However, the electrical connection thus made through the collaboration of these two connectors is not satisfactory because it is too easy to unclip.
In order to measure the extraction force needed to unclip a connection, it is possible to use a tensile testing machine and apply tension to the electrical connection.
Laboratory tests have shown that the average insertion-force value for so-called “power” connections, for example for heating, is 56.5 N, but that the average extraction-force value for these power connections is 64.2 N, which is very similar.
It is preferable for the extraction-force value to be reasonable, in order to allow the glazing to be changed if necessary without the need to change the female electrical connector, but such a small difference between the two opposing force values is unacceptable because it means that there is a risk that the female connector will all too readily become unclipped from the male connector.
Admittedly, it is possible to encapsulate the electrical connection in a plastic but then it becomes impossible to change the glazing without changing the female connector: when the glazing is changed, the entire electrical connection has also to be changed, this of course increasing the cost of the replacement glazing.